Shaker conveyer



S HAKER CONVEYER Filed April 15, 1931 MHZ/V70? 76 49 50/196 ATTORNEY Patented June 2Q, 1933 urran STATES PATENT OFFICE,

TAGE enone NYBORG, or woncnstrnn, ENGLAND, assrenoiaor onn- ALFro MARK FREDERICK HIGGINS, or woacns'rnn, ENG-LAND sHaKEa convnvna Application filed April 13', 1931, Serial No. 529,828, and in Great Britain May a, 1930.

This invention relates to shaker conveyers and relates more particularly to that type of conveyer in which the reciprocations of the conveyer are derived from a rotary member through a crank and connecting rod mecha: nism.

In this type of mechanism, the obliquity of the relatively short connecting rod gives rise to considerable difference in the accelerave er. I m

in a usualconstruction, the end of the connecting rod remote from the crankpin only reaches its maximum velocity after two thirds of the "forward stroke which means that the forward acceleration is of much lower value than the subsequent deceleration, and conversely in the returnlstroke the initial increase in speed is sharp and the subsequent decrease in speed more gradual. For the practical operation of the shaker conveyer it is desirable to ensure that the deceleration at the end of the forward stroke of the conveyershall be sharp enough to ensure dislodgment of the material i. e. shall 7 exceed the friction of the material on the trays. According to the present invention, the period' of maximum velocity and 'valueof deceleration at theend 'of the forward stroke is increased by providing in the mechanism a certain amount ofloose motion or slogger between the cross-head which derives its rc-x ciprocation direct from the connecting rod and the member which is connected to the conveyer. I 1

Incidentally, this provision will slightly diminish the value of acceleration at the be ginning of bothstrokes (which is a favourable circumstance) and will also slightly increase the value of the deceleration at the end of the return stroke; but this latter increase owing to the extended duration of this deceleration may be neglected.

The invention is illustrated in the acconr panying drawing in which thesole figure, illustrates an embodiment in which the present invention isshown as an improved form of a mechanism which is otherwise already known. i

tion at the two ends of the stroke of the con- In the form illustrated, the crosshead 1 is understood tobe reciprocated from left to right in a suitable slideway by means of a short crank articulated by a connecting rod to the transverse pivot 2. The conveyer troughs are coupled to a second cross-head 3, by means of a transverse pivot 4. The drive from cross-head 1 both forwardly and rearwardly is transmitted to cross-head 3 through the intermediary of a strong compression spring 5 engaged between collars 6, 7, bearing against a shoulder 8 integral with cross-head 3, and a boss 9 detachably mounted on the taillO of cross-head 3 by means of ascrew thread, the parts being locked by a grub screw 11, split pin or the like.

The collars 6, 7, are driven rearwardly and forwardly by internal shoulders formed on the casing 12 integral with the crosshead 1.

Now according to the present invention a certain amount of slogger or loose motion is introduced between the two pivots 2, 4. This loose motion, in the form shown, is provided between the collars 6, 7, and the engaging faces of the casing 12. The drawing shows the parts in a mid position and the total amount of loose motion is represented by the two gaps a and b. In order thatthis amount of loose motion may be varied, the engaging face of the casing 12 at one end iscomprised by an adjustable threaded sleeve 13 received into the threaded end of the casing and adapted to be locked in any position to which it has been set by a lock nut 14.

lVith the above construction it will be realized generally that as the cross-head 1 moves to the right in the figure, after it has reached its maximum velocity and begins to decelerate, the cross-head 3 will be projected forward relatively to the cross-head 1 by an amount depending on the inertia of the moving parts of the conveyerand alsoupon the extent to which the spring 5 has been compressed. After receiving't-he amount of lead permitted by the gaps aand I), it will then be suddenly decelerated owing to the engagement of the forward collar'6 with the collar 13 at a time when the forward velocity of the cross-head 1 is rapidly'declining to ero.

its rate of change of velocity, i. e. deceleration, reaches such a higlrvalue that the friction of the material in the trays is overcome. Thus, with the present invention, the dislodgment of the material occurs at a time when its kinetic energy (r fl Mv is much higher than is the case without slogger; the invention is thus equivalentto the provision of a crank of substantially increased length giving a substantially increased stroke to pin 2. f

" In the'reverse direction, the initial move- 7 ment of the cross-head 3-will correspond generallykvith that of'cross-head land have a sharp acceleration reaching 'a'm'airimum at about one third of the stroke. After this point the cross-head 3 will move freely under its; own inertia as the cross-head begins to decelerate, but as, deceleration of the cross head 1 commences early and lasts for an extended period on thereverse strokethe'variation'between thetwo'speeds will not be so: pronounced as in the forward stroke, and will be of no practical effect on thematerial.

It will be understood that the sudden deceleration on the forward stroke shifts the material in the eonveyer and that the acceleration on therearward stroke, being steadied or softened by being transmitted through the spring 5, is insuflicient, to dislodge the material, the conveyer.

From the above description it will be realized that the invention provides for a short deceleration at the end of the forward stroke by providing in the mechanism a certaintoan actuating shoulder; and that the drive transmitted by theresilient linkin both directions is only taken up by an "actuating shoulder after a; certain amount of loose motion onthe part of a driving abutment by reason of the provision of the gaps a, b.

I claim i w 1-. Amember to be interposed between the drivingmeans and" trough of a shaking conveyer, comprising relatively slidable elements connected respectively'to the driving means and to the trough, abutments slidable on one member, a coiled spring encircling such member and arranged between the abutments, and means on the respective elements for cooperating -with the abutments to control the spring relation between the elements, said means constituting a lost motion with respect to the abutments.

2. A member to be interposed between the driving means and trough of a shaking conveyer, comprising relatively slidable elements connected respectively to the driving means and to the trough, abutments slidable on one member, a coiled spring encircling such member and arranged between the abutments, and relatively adjustable means onthe respective elements for cooperating with the abutments to control the spring relation between the elements, said means-constituting a lost motion with respect to the abutments.

3, An actuating means to be arranged between the power elements and the trough of a shaking conveyer, including a driving member and a driven member connected for relatively free limited play in the power direction, a spring carried by one of the members and responsive to relative movement of both members to take up the free play under the driving movement of the driving member and yield such free play to the driven member at the limit of driving action, and means intermediate the spring and driving and driven members to cause the yielding of the free play to the driven member to permit movement thereof free of the driving member and to the extent of such free play at a rate of travel substantially equaling the {)naximum rate of travel of the driving mem- 4. A means for actuating the trough of a shaking conveyer from the power means, ineluding a driving member, a driven member, said members being arranged for relatively free limited play in the direction of driving movement, a spring carried by one of the members, abutments carried at the respective ends of the spring, andmeans on the driving member and driven member to operate through the spring for taking up the free play between said members during driving action and yield that free play to the driven member at the limit of driving action, the relation of themeans on said members permitting the driven member when moving under the free play permitted to move at a rate substantially equaling the maximum rate of the driving member.

5. A means for actuating the trough of a shaking conveyer from the power means, in cludinga driving member, a driven member, said members being arranged for relatively free limited play in the direction of driving movement, a spring carried by one of the members, abutments carried at the respective ends of the spring, and adjustable means on the driving member and driven member to operate through the spring for on saidmembers permitting the driven member When moving under the free play permitted to move at a rate substantially equaling the maximum rate of the driving member.

6Q A means for actuating the trough of a" shaking conveyer from the power means, including a driving member, a driven member, said members being arranged for relatively limited free play in the direction of driving movement, a spring carried by one of the members, abutments carried at the respective ends of the spring and means on the driving member and driven member to operate through thespring for taking up the free play between said members during driving action and yield that free play to the driven member at the limit of driving action, the relation of the means on said members permitting the driven member when moving under the free play permitted to move at a rate substantially equaling the maximum rate of the driving member, the cooperation of said means and abutments providing a sharply defined deceleration of such driven member at the limit of such free play movement. V In testimony whereof I afiix my signature.

TAGE GEORG NYBORG. 

